A rill in a barnyard and the Grand Canyon represent, in the main, stages of valley erosion that began some millions of years apart.

The meaning that we are seeking in evolution is its meaning to us, to man. The ethics of evolution must be human ethics. It is one of the many unique qualities of man, the new sort of animal, that he is the only ethical animal. The ethical need and its fulfillment are also products of evolution, but they have been produced in man alone.

I have a debt, a loyalty to the museum; the best place for me to do what I wanted to do.

Most of the dogmatic religions have exhibited a perverse talent for taking the wrong side on the most important concepts in the material universe, from the structure of the solar system to the origin of man.

If a sect does officially insist that its structure of belief demands that evolution be false, then no compromise is possible. An honest and competent biology teacher can only conclude that the sect's beliefs are wrong and that its religion is a false one.

The fact -- not theory -- that evolution has occurred and the Darwinian theory as to how it occurred have become so confused in popular opinion that the distinction must be stressed.

Man is the result of a purposeless and natural process that did not have him in mind